Sewing-machine



H. CORRALL.

SEWING MACHINE.

APPLICATION FILED nov. 23. 915.

1 3 1 3,265 Patented Aug. 19,1919.

WITNESSES:

6 zw Q/QJD UNITED STATES.

PATENT OFFICE.

HERBERT GORBALL, OF HELENSBURGI-I, SCOTLAND, ASSTGNOR TO THE SINGER MAN U- EACTURING- COMPANY, A CORPORATION OF NEW JERSEY.

SEWING-MACHINE.

To all whom it may concern: 7

Be it known that I, HERBERT CORRALL, a subject of theKing of the United Kingdom of Great Britain and Ireland, and residing at Parkview, Helensburgh, Dumbartonshire, Scotland, have invented certain new and useful Improvements in Sewing-lilachines, of which the following is a specification, reference being had therein to the accompanying drawings.

V This invention relates to sewing machines, being particularly applicable to machines for sock darni'ng, patching and the like, and has for its primary object to provide improved presser-bar actuating mechanism which will permit of control of the pressure to suit the thiclmess of the goods and insure silent running at high speeds, and will be less subject to wear and tear, by reason of the elimination of the shocks towhich the moving parts of machines of this class are subjected.

In the present embodiment of the invention av block is. slidably mounted upon the presser-bar of themachine and is engaged by upper and lower spiral springs, surrounding and movable with the bar. The block is engaged bythe arm of a rocker so operated by .link and lever connections with an BC.-

centric on the driving shaft that the presser bar is normally held raised but is depressed and held at rest upon the work during the movement of the needle therein.

In the accompanying'drawings, Figure 1 is an end elevation showing the head of a sewing machine embodying the invention; Fig. 2 is a sectional plan showing the connections for operating thev presser-bar, and Fig. 3 is a detail view of certain of said con-' nections, y l

Mounted to slide vertically on the presserbar is a block 2 above and below which are collars 3, 3 fixed onrthe presser-bar. Interposed between the block 2 and the upper collar 3 is a helical spring 4 surrounding the Presser-bar: interposed between the block 2 and the lower collar 3' is a spring 4' also surrounding the presser-bar. springs 41; and 4: thus constitute a yielding connection between the block 2 and the presser-bar through the collars 3 and 3 which afi'ord thrust-receiving shoulders upon the presser-bar.

The block 2thus constitutes a floating member deriving vertical reciprocating Specification of Letters Patent.

The

Patented Aug. 19, 1919.

Application filed November 23, 1915. Serial No. 63,101.

movements from a train of connections herev is caused to descend the presser-bar 1 will in the first place be moved therewith, said springs 4, 4 beingsu'bstantially in equilibrium. When, however, the presser-foot 5 engages the work, so that resistance is offered to the downward movement of the resser-bar, the lower; spring 4 is compressed while the upper spring t expands, the block 2 remaining under the control of the springs 4:, 4L. 1

The compression of the spring 4 will evidently be proportional to thethickness of the goods engaged by the presser-bar 1,. so that the pressure on the goods is proportionate to the weight of the material being handled.

The block 2 is formed with guideways (i entered byslide plates 7 formed with substantially circular sockets receiving the substantially circular ends ofthe .forked arm or rocker 8 carried bya shaft 9 parallel with and driven from the main-shaft 10 as herein- -after referred to; the reciprocation of the ,washed out by lubricant. The lower'opening of the duct is normally covered by a wall of the block, but is exposed when the block is depressed to lower the presser-bar,

asshown in Fig. 1.

The presser-bar is surrounded at its upper end by a cushion. spring 12 and an adjustable collar 13 serves to engage the spring and thus to check the bar land insure quiet running at high speed on very thin mate rial.

' The shaft 9 is actuatedtrom an eccentric 11011 the main-shaft 10 through suitable connections as fo1lows:- I I Mounted on the main-shaft 10 is the eccentrio 14 embraced by the strap 15* of an ec-" centric rod 15 which is connected at 16 to the end of the short arm 17 of rock+lever 18 loesely mounted. upon the 11.11am pin 19.

The rock-lever 18 is connected at 20' with the lower end of a link 21, the opposite end of the link being connected to a crank-arm 22 on the shaft 9.

It will be seen from inspection of Fig. 1 that endwise reciprocation of eccentric rod 15 will swing the lower end of link 21 in a short arcuate path and subsequently will move the link bodily. As indicated in the said figure, the idle movement of the link is within the points 2 -0". In the movement of link 21 to the right from the position shown in Fig. l and until it passes the point z" the presser-foot is held in engagement with the work. Immediately thereafter however, the needle rises abovev the work and link 21 is given a bodily upward movement by lever 18 to rock the shaft 9 and elevate block 2 with the presser-bar.

IIaving thus set forth the nature of the invention, what I claim herein is 1. In a sewing machine, the combination with a presserbar, of a block slidably mounted on the said bar, oppositely-acting springs engaging the block, and means to impart up and down movements to the said block and thereby to the said bar.

2 In a sewing machine, the combination with a presser-bar, of a block slidably mounted on the said bar, oppositely-acting springs engaging the block, an element operatively connected with the said block for imparting up and down movements thereto, and means adapted to alternately actuate said element and hold the same in a state of rest for a predetermined period.

3. In a sewing machine, in combination, a

. presser-bar and a resser-foot carried thereby, a reciprocatory member mounted upon said presser-bar and yieldingly maintained in operative t-ion therewith, and means including a common element for actuating said reciprocatory member to raise and hold the presser-bar in elevated position and to forcibly depress and hold said bar in lowered position respectively during predetermined intervals.

4. In a sewing machine, the combination with a frame and a Presser-bar mounted for endwise movement therein, of a shaft, an eccentric element on the said shaft, a rocklever, an operative connection between the rock-lever and said eccentric element, a lifting arm operatively connected with the presser-bar, and a connection between the said rock-lever and the lifting arm including a link arranged to swing idly during part of the movement of said rock-lever.

5. In a sewing machine, the combination with a Presser-bar, of a block slidably mounted on said bar, oppositely-acting springs surrounding the bar and engaging the said block, slides movable on the block transversely of the bar and a rocking member engaging said slides and imparting up and down movements to said block and thereby to the said bar.

6. In a sewing machine, the combination with a resser-bar formed with a longitudinal lubricant duct, a block slidably mounted upon the said bar, oppositely-acting springs surrolmdiiig said bar and engaging said block, and means for impartmg up and down movements to said block to alternately elevate and depress the bar and also to alternately expose and cover one end of said duct.

7. In a. sewing machine, the combination with a frame and a work-plate supported thereon, of a resser-bar and a presser foot carried thereby, and common means including a yielding element for lifting saidpresser-bar during one period of the cycle and for forcing the resser-foot yieldingly against the work with a pressure proportionate to the thickness of the work during another period of the cycle.

8. In a sewing machine, in combination, a reciprocatory element, a presser-bar, and 0ppositely acting springs connecting said element with said bar.

In testimony whereof I have signed my name to this specification in the presence of Copies of this patent may be obtained. for five cents each, by addressing the Commissioner of Patents,

Washington, D. G. 

